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Mon Mar 13 13:13:10 2000

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[ Oran/NASAChatHost - 8 - 10:00:26 ]
Hello and welcome to today's NASA Quest Space Team Online/Classroom Connect panel discussion with NASA experts! Today's panel discussion features: Frank Merceret, a meteorologist from NASA Kennedy Space Center; Ken Schrock, an engineer from NASA Marshall Space Flight Center, Leslie Ringo, a flight simulation engineer from NASA Ames Research Center; and Andrew Petro, a space craft design engineer from NASA Johnson Space Center.

[ Oran/NASAChatHost - 9 - 10:01:03 ]
And now, here are our panelists to answer your questions.

[ Frank/KSCWeatherOffice - 13 - 10:03:18 ]
RE: [Ellen] How hard is it to land the Space Shuttle if it is a really rainy day? asks Jack Sweeney, 1st grade
Jack - A good question! The Shuttle cannot land in the rain. The Shuttle flies very fast, even when it is landing. The raindrops hitting the Shuttle's heat-resistant tiles at that speed would hurt them, and it would cost a lot of money to repair. For that reason, we do not land Shuttles in the rain. Frank

[ Leslie_Ringo - 16 - 10:04:28 ]
RE: [Ellen] How hard is it to land the Space Shuttle if it is a really rainy day? asks Jack Sweeney, 1st grade
The Space Shuttle has several alternate landing sites should Kennedy Space Center have a rainy day. It is possible to land at a wet runway, but the NASA officials will always look for a safer runway.

[ Leslie_Ringo - 17 - 10:06:50 ]
RE: [Ellen] How cold is it in space?
As to how cold it is in space, it is -400 F to 400 F depending whether you are in sun or not according to astronaut Alan Poindexter who is here currently at the NASA Ames VMS lab.

[ Frank/KSCWeatherOffice - 19 - 10:08:21 ]
RE: [Ellen] Hello. We are are first grade class from Wilkinson Elementary in Sarasota Florida. We have a question for Mr. Frank Merceret. What type of weather would affect the launch of a space shuttle the most and why?
Hello Wilkkinson Elementary! There are many weather phenomena that can delay or prevent the launch of a Shuttle. One of them is rain - I've already discussed that in response to another question. Another one is lightning. If lightning hit the Shuttle while it was being launched it could cause a major accident. We have a long list of what we call "lightning launch commit criteria". These are rules about avoiding the kinds of clouds in which lightning could occur. If these kinds of clouds are over or near the launch pad, we cannot launch. There are also constraints on the winds. At the surface, the winds cannot exceed certain limits that might cause the vehicle to blow against the structure when it launches, or might prevent a return to launch site landing in an emergency. Upper air winds cannot change too much or the guidance commands in the vehicle might not be able to properly control the Shuttle. We have carefully made rules for all of these things. Frank

[ Leslie_Ringo - 24 - 10:09:02 ]
Currently, at the world's largest vertical motion simulator (VMS) we are training astronauts for the approach and landing phase of a shuttle mission. I can answer any questions about this fabulous simulator or the training we are currently doing.

[ AndyPetro/JSC - 25 - 10:09:04 ]
RE: [marilyn] We are curious about the terminolgy that is used when the shuttle is communicating with the ground. Does this change after the launch? What is the correct terminology when approaching another space vehicle for docking? Is the word 'translation' used for moving the shuttle towards another object? Thank You Marilyn
Translation is the right word for when the Shuttle moves along in one direction (up, down, right, left, forward, backward. Rotation is when the Shuttle turns around without translating.

[ Leslie_Ringo - 27 - 10:10:03 ]
RE: [Regina] How do you like your job?
I loooooove my job! I get to play in the world largest simulator and they pay me to support it! :)

[ AndyPetro/JSC - 29 - 10:11:18 ]
RE: [Ellen8] Dear Mr. Petro Did you work on the new Venture Star Shuttle?
No, I do not work on Venture Star. That is a project of the Lockheed Martin company. They are working on an experimental version of Venture Star in a partnership with NASA but most of NASA's part of it is at the Marshall Space Flight Center.

[ Frank/KSCWeatherOffice - 30 - 10:11:39 ]
RE: [RyanNashuaNH] Has the space shuttle been damaged by storms?
Ryan - Several of the Shuttle orbiters have sustained minor damage at one time or another due to things like hail at the pad, or flying through rain while on top of the Shuttle carrier aircraft while returning to KSC from the west coast (our weather forecasting is NOT perfect yet!). This has not happened often and the damage has not been severe. Frank

[ Leslie_Ringo - 35 - 10:12:41 ]
RE: [Kelly] Dear Mike Moss, What is the most serious system that has shut down while you were monitoring it? How did you react? Did everything turn out all right? 8th grade
Just in case Mr. Moss has not logged on, I'll answer my best guess. To my understanding, the most serious systems on the space shuttle are the engines. Launch is the most dangerous phase of a shuttle mission. Next would be the auxilary power units (APU) which controls several systems on the shuttle.

[ Leslie_Ringo - 36 - 10:13:21 ]
RE: [terraMelanie5thgrade] Leslie, is it really hard to land a shuttle in a tornado?
Yes.

[ AndyPetro/JSC - 40 - 10:15:06 ]
RE: [DeniseHanbys3rdGrade/IrwinCoElem] Does your space ship feel HOT when you get near the sun?
When a spaceship goes into orbit around the Earth is only a few hundred miles closer to the sun than we are - and the sun is 93 million miles away. The side of a spaceship facing the sun does get very hot but that is because in space there is no air to shield it from the sun's rays - not because it is closer to the sun.

[ Leslie_Ringo - 41 - 10:15:33 ]
RE: [soehlms] Leslie: Students here at Soehl MS would like to hear about the training that astronauts do, and the length of training they need before actually going on a mission?
The astronauts will fly to NASA Ames for a day and then they will spend half a day in our simulator training. We will give them failures such as blown tires, failed APUs, strong cross winds, failed chutes and so on. They do about 20 consecutive runs before calling it a day.

[ Frank/KSCWeatherOffice - 42 - 10:16:22 ]
RE: [Regina] How do you like your job?
Regina - I don't know if you wanted me or someone else to answer that, but I am always delighted to answer a question like that. I LOVE MY JOB! Human spaceflight is ultimately necessary if humanity is to survive. We are running out of resources here on Earth, but space is full of them. Eventually, Earth will get hit with a comet or the sun will go nova -- but spaceflight will give us the power to deflect the comet, or move ourselves to another star system. This work is vitally important to the survival of humanity, and I'm proud to be part of it. Not only that -- the people are great to work with. Everything is a team effort, and people work together. And, finally, we do it well. People all over the world come to NASA for guidance and advice because of our expertise. We can take great pride in that. Frank

[ AndyPetro/JSC - 43 - 10:17:05 ]
RE: [GailandLindsay] Dear Mr. Petro, Is the light from the Earth brighter in space?
The light from the sun is brighter in space because there is no air to absorb it. The light from the Earth is only what the Earth reflects from the sun.

[ Leslie_Ringo - 44 - 10:17:06 ]
RE: [soehlms] Leslie: Students here at Soehl MS would like to hear about the training that astronauts do, and the length of training they need before actually going on a mission?
The amount of training all astronauts receive is 2 years of just general training, and then another 1-2 years of training when they are assigned to a mission. For the landing and rollout training we provide at NASA Ames, the astronauts come out twice a year.

[ Leslie_Ringo - 52 - 10:19:40 ]
RE: [terraMelanie5thgrade] LESLIE,WHAT IS THE HARDEST WEATHER TO LAND A SHUTTLE?
The weather limit is a 17 knot cross wind in which the space shuttle can land. The lowest visibility conditions are a 10000 ft ceiling with 7 miles of visibility.

[ AndyPetro/JSC - 53 - 10:20:12 ]
RE: [Leslie_Ringo] The astronauts will fly to NASA Ames for a day and then they will spend half a day in our simulator training. We will give them failures such as blown tires, failed APUs, strong cross winds, failed chutes and so on. They do about 20 consecutive runs before calling it a day.
I'd like to add that the Shuttle astronauts spend at least a year working full time on their training for a mission. A lot of that is spent in mission rehearsals in flight simulators at the Johnson Space Center.

[ AndyPetro/JSC - 54 - 10:20:44 ]
RE: [Tory] If I were to go into space in a shuttle, would I be harmed if I wore ordinary clothing?
You would be fine as long as you stayed inside the Shuttle.

[ Leslie_Ringo - 55 - 10:21:35 ]
RE: [KayleeandAmie] Leslie Ringo, how many times have you been in space?
I wish I had been into space. My job is a flight simulation engineer. I only work with astronauts. I suppose if I go back to school and get a PhD degree and apply to be an astronaut, I could have a chance to see space.

[ AndyPetro/JSC - 56 - 10:22:00 ]
RE: [Tory] How many shuttle missions have been taken, and were any unsuccessful?
There have been about 100 shuttle missions. Only one was a complete failure (in 1986).

[ AndyPetro/JSC - 57 - 10:23:19 ]
RE: [soehlms] Andrew: Soehl MS students here would like to know what kind of schooling YOU went through to design spacecrafts!?
I got a degree in aerospace engineering. Then there is a lot of on-the-job training.

[ Leslie_Ringo - 58 - 10:23:55 ]
RE: [Regina] What experiences have you had from your job?
The best experiences I have had from my job are the various airplanes that I have helped to simulate. I have flown (in the simulator) the Comanche helicopter, Blackhawk helicopter, Space Shuttle, and Joint Strike Fighter. Never a dull moment at my job.

[ AndyPetro/JSC - 59 - 10:24:45 ]
RE: [GailandLindsay] Dear Mr. Petro is it hot inside of the capsule when it falls in the water?
It does get warm because of the heat caused by friction when a capsule (or the Shuttle) flies back through the atmosphere. But the inside is kept cool enough for the people to remain healthy.

[ KenSchrock/MSFC - 67 - 10:26:14 ]
RE: [Randy] Mr. Schrock has a shuttle radio ever broke in space?
I'm afraid I don't know how many times a radio has broke. Part of good engineering design is to have redundancy built in, not for if something breaks, but rather when something breaks. Even a Cessna 152, like you may take flying lessons in usually has two radios. Between HF, VHF, UHF radios built in to the shuttle, there is also the radar track and telemetry up and down to the shuttle that could be used for communications. There are sites all over the world that are staffed just in case there is some trouble with communications, that can "talk" with the shuttle as it flies overhead.

[ AndyPetro/JSC - 68 - 10:27:12 ]
RE: [KayleeandAmie] Can you get candy in space?
Sure. You can take lots of different kinds of food. The astronauts usually have M&M's to eat.

[ AndyPetro/JSC - 70 - 10:28:04 ]
RE: [KayleeandAmie] If I could afford to go to space, could I at the age of 13?
I see no reason why you could not. Maybe someday it will be inexpensive enough for all of us to go.

[ Leslie_Ringo - 71 - 10:28:04 ]
RE: [jennifer] has the landing gears ever gave out?
When we train in our simulators, we do not simulate the landing gear not correctly deploying. I believe they have some back up devices (pyros?) to deploy the landing gear should it not correctly extend with the gear mechanisms.

[ Frank/KSCWeatherOffice - 72 - 10:28:51 ]
RE: [Regina] What experiences have you had from your job?
Regina - I don't know to whom you are directing this question, but I'll take a shot at it. My work is in weather research, not forecasting (the Air Force and the National Weather Service do all of the Shuttle forecasting) -- but I have had the pleasure of solving several weather problems for Shuttle. For example, when the program thought it might need to change its wind criteria for launch, I did a large part of the research which enabled them to avoid the unnecessary expense by showing that what they had was OK. I have helped the Air Force and National Weather Service understand some strange weather radar images during launch countdowns. I have published quite a few research papers on upper air wind measurements which is leading to new capabilities for Shuttle to use this data. There's a lot more, but I hope you get the picture!

[ Leslie_Ringo - 73 - 10:29:36 ]
RE: [Ashley] How much education is needed for your type of profession you do?
For my job, it really only required an BS degree in Engineering and a desire to work with aircraft and simulations. A strong computer programming background has been the most important tool from my education.

[ AndyPetro/JSC - 74 - 10:29:48 ]
RE: [Kelly] Andrew Petro, Is their an upcoming project that you are especially excited about? 8th grade
Yes, the one I am working on now is a plasma rocket which is a new kind of electric rocket which we might use on spaceships going to Mars and other planets. It could get us there much faster than any rocket we have now. We hope to test it in space in a few years.

[ Leslie_Ringo - 85 - 10:32:25 ]
RE: [Barbara8thgrade] Is NASA beginning to select less and less astronauts to train, and training more and more from special segments of the populus or industry?
Actually, NASA has been selecting more and more astronauts these past couple of years. The main reason is NASA is getting ready to support Space Station Operations and this is the time to get their many years of training in before the Space Station is 100% operational.

[ AndyPetro/JSC - 86 - 10:32:44 ]
RE: [GailandLindsay] Dear Mr. Petro do you sleep for and at the same time as on Earth?
From what I hear, astronauts sleep a little less in space than they do on the ground but they still need it. They usually sleep during the nighttime in Houston (where mission control is) unless they are wrking in shifts around the clock. Then they work in teams and take turns sleeeping.

[ Frank/KSCWeatherOffice - 87 - 10:33:35 ]
RE: [MissFiskesFourth] What courses would we take to persue a career in meteorology?
Ashley and Miss Fiske's Fourth - your questions tie together. Meteorology is a branch of physics. A strong background in mathematics and physics is essential. Courses in engineering and computers can also help a lot. Forecasters can usualy get by with a Batchellor's degree. Research meteorologists and many forecast specialists need a Master's or Ph.D. (For my job, the Ph.D. is required). I would also stress the importance of being able to communicate well. reading, writing and speaking are how we communicate with our customers. The best forecast or research is useless unless it is effectively communicated to the customer. Don't neglect those writing and speaking courses!

[ AndyPetro/JSC - 88 - 10:33:50 ]
RE: [Barbara8thgrade] Is NASA beginning to select less and less astronauts to train, and training more and more from special segments of the populus or industry?
No, i think they are selecting astronauts at about the same rate. There will be an increasing need for specialists as work on the space station increases.

[ KenSchrock/MSFC - 89 - 10:34:12 ]
RE: [jennifer] has the landing gears ever gave out?
I've never heard of the landing gears giving out. If something like that were to happen, it would be all over the news. However, I'll play along with the idea that the landing gears didn't work. If they could tell from orbit that there was a problem, they would probably try to divert the landing to NASA Dryden at Edwards Air Force Base. There they have a 35,000 foot long landing strip on a dry lake bed. The lake bed is softer than the concrete or asphalt, and therefore would cause less damage to the shuttle. The pilot would bring it in with gears up, landing nose high. You would rather drag some of the back off than take a chance that the nose could dig in and flip the shuttle forward. I believe the landing speed would be about 200 miles per hour, so flipping around would not be good. The reason they have done so many experimental flights at Edwards Air Force Base is because they have that long lakebed to give the pilot every opportunity to land as safely as possible.

[ Leslie_Ringo - 90 - 10:34:24 ]
RE: [Tory] Do you see yourself ever going into space, Mrs. Ringo?
I won't deny that if I was offered the opportunity, I would take the opportunity to fly in space. Unfortunately, I do not have the required skills to allow me to join the astronaut corps. You need to start very early to aim for such a career. I suggest you start planning now if you want to travel to Mars. :)

[ Frank/KSCWeatherOffice - 91 - 10:34:44 ]
RE: [BrittnyNashuaNH] Frank, have you ever been inside the space shuttle?
Brittany - Only on the ground!

[ AndyPetro/JSC - 92 - 10:35:15 ]
RE: [GailandLindsay] Mr. Petro do you eat freeze dried food or solid real food?
I'm not an astronaut but in space they eat some freeze-dried food but a lot of it is just normal food. They just have to avoid things that cause a lot of crumbs.

[ AndyPetro/JSC - 93 - 10:36:48 ]
RE: [GailandLindsay] Dear Mr. petro How do you go to the bathroom?
Again, I'm not an astronaut but in space they use a special toilet that uses the flow of air to make the liquid and solid waste move along into a container. Otherwise its pretty much like using the bathroom on Earth.

[ Frank/KSCWeatherOffice - 94 - 10:38:13 ]
RE: [Amypaul] Under what certain circumstances would a space shuttle be canceled?
A Shuttle launch can be cancelled for a variety of reasons. There may be a problem with the Shuttle or its booster rockets. The launch would be cancelled until the problem was fixed. The payload that the Shuttle is carrying might need repair. Finally, the weather might not permit launch (for example, if there were thunderstorms over the launch site.)

[ AndyPetro/JSC - 100 - 10:39:52 ]
RE: [marilyn] We have received some conflicting information from an expert at JSC told me that in space one cannot see stars with the naked eye because the human eye cannot resolve a pin point of light. But an astronaut at Kennedy said he saw stars durning his mission. What is the scoop? Did he see Madona?
I have always heard astronauts say that the stars are visible and very bright in space - like seeing the stars from a mountain on a clear night or even better.

[ AndyPetro/JSC - 101 - 10:41:08 ]
RE: [Amypaul] At top speed, how fast can the shuttle go?
In space the shuttle goes about 18,000 miles per hour. When it enters the atmosphere it is going 25 times the speed of sound.

[ Leslie_Ringo - 102 - 10:41:13 ]
RE: [marilyn] We have received some conflicting information from an expert at JSC told me that in space one cannot see stars with the naked eye because the human eye cannot resolve a pin point of light. But an astronaut at Kennedy said he saw stars durning his mission. What is the scoop? Did he see Madona?
You need to be able to see the stars in space. On the orbitor, they have "Star Trackers" that require seeing the stars in order to work. These Star Trackers are used to provide important navigation information to the Space Shuttle.

[ KenSchrock/MSFC - 103 - 10:41:32 ]
RE: [soehlms] Ken: Where can a student go on the web to get the GPS of any place on Earth?
I would start at navcen.uscg.mil which is the site for civilians (non-military) to get official information on the satellites. They have two things that I go to get from there. One is almanacs of where the satellites are supposed to be and if there are any scheduled events that would make some of them unusable. The other thing to get is the ephemeris data, which is very precise information about the orbits. GPS works by taking the position of the satellite and the time it takes for a signal to get from a satellite to you. The time gives the distance, and your GPS receiver uses lots of geometry and algebra to figure out where you are. The almanacs and ephemeris help you to get the best possible answer. Sometimes in engineering we can get multiple answers and we have to decide which is best. Best doesn't always mean the most accurate. Sometimes you have to make choices between accuracy and time. In others words sometimes you have to decide what is good enough, without going in to overkill.

[ Frank/KSCWeatherOffice - 104 - 10:42:47 ]
RE: [Randy] Has a bad storm occurred during a shuttle in space Mr. Merceret
Randy - In space there is no "weather" of the usual kind because there is no air to make wind, no water vapor to make clouds. "space weather" has to do with solar flares and radiation and stuff I don't know much about. For launches and landings, we have many rules that keep us safe by not letting us launch or land in bad weather -- so there has not been a bad storm which affected a shuttle while in flight.

[ AndyPetro/JSC - 105 - 10:43:51 ]
RE: [Ashley] How long does it take to prepare a space shuttle for launching?
It takes a few months from the time it lands until it is ready to launch again. But the payloads that are put into the Shuttle can take years to get ready.

[ Frank/KSCWeatherOffice - 106 - 10:43:56 ]
RE: [Tory] What experiment has been the most successful that has been conducted in space?
Tory - I vote for the Hubble Telescope! Frank

[ Leslie_Ringo - 107 - 10:44:06 ]
RE: [Jennifer] Leslie, can you describe the basics of how the VMS works? Do the astronauts get inside? Do they need to be strapped in or can they move around?
The VMS is located within this large tower. Inside of the tower, we have a cab that the astronauts sit inside and are strapped in. When in motion, they can move up and down the same distance that is equivalent to a 6 story building and a 4 story building for moving left and right. In addition you can move forward and back, and roll, pitch and yaw. For even more information and pictures, check out http://www.simlabs.arc.nasa.gov.

[ AndyPetro/JSC - 119 - 10:46:45 ]
RE: [Gailandlindsay] Is the equipment heavy or is any of it wood?8th
Can you ask your question again and say what equipment you are asking about?

[ Leslie_Ringo - 120 - 10:47:45 ]
RE: [Gailandlindsay] Is the equipment heavy or is any of it wood?8th
If it is equiment flying on the Space Shuttle, it needs to be a very sturdy "flight qualified" material, and I don't believe wood would count.

[ KenSchrock/MSFC - 121 - 10:47:50 ]
RE: [Tory] What experiment has been the most successful that has been conducted in space?
We haven't got the data back yet, but I've read in magazines like, "Aviation Week and Space Technology" that the recent Shuttle Radar Topography Mission (I think that was the name) was one of the most important shuttle missions, because it will give us better elevation data for the entire planet than we have ever had. I'm sure there would be many who would say that the Apollo missions were most important because they proved that we had the technology to begin sending people to explore something outside of the earth.

[ AndyPetro/JSC - 122 - 10:47:56 ]
RE: [Kate] How big is the space shuttle?
It is about 120 feet long. About the size of a medium sized airliner. A school bus would fit inside the payload bay.

[ Frank/KSCWeatherOffice - 123 - 10:47:59 ]
RE: [Randy] Leslie has a shuttle crashed while landing
No

[ AndyPetro/JSC - 124 - 10:48:21 ]
RE: [Tory] How old is John Glenn?
I think he is 79.

[ Leslie_Ringo - 125 - 10:49:25 ]
RE: [Randy] Leslie has a shuttle crashed while landing
No, the shuttle has never crashed during a landing. The only time I have ever seen a shuttle crash is when a non-astronaut pilot was flying the shuttle in the simulator. Remember, the astronauts train for years and years to avoid anything remotely near to what you would call a "crash."

[ AndyPetro/JSC - 126 - 10:49:40 ]
RE: [Ashley] Do your families live there at Nasa with you or how often do you get to see them?
Working at NASA is like a regular job in many ways. People live with their families in the neighborhoods around the centers.

[ Leslie_Ringo - 128 - 10:51:28 ]
RE: [marilyn] When the shuttle is in space and is talking to the ground do they say, "Houston, this in Columbia?" or is Houston not the correct word?
From the shuttle to JSC, they will say "Houston, Columbia (and then the question)". From ground control to the shuttle, they will say "Columbia, Houston (adding what information that needs to be passed on.)

[ KenSchrock/MSFC - 130 - 10:53:48 ]
RE: [Brian] Dear Mr. Schrock, What is an X-plane, and do you work on them?
The X stands for eXperimental and they are always the first of a type of vehicle that started with a theory that needs investigating. You could call the Wright Brothers airplane an X vehicle because they used it to test theories and further the knowledge base of the design of aerospace vehicles. The first numbered X vehicle was the X-1 which Chuck Yeager flew to supersonic (greater than Mach 1) speeds. I'm currently associated with X-33, -34, -37 and 40A X vehicles. All of these are reusable launch vehicle demonstrators. X-31 and X-36 were out at Dryden when I was there, but I didn't work with them much. They were more focused on aircraft maneuvarability investigations.

[ Leslie_Ringo - 131 - 10:55:01 ]
RE: [Tory] Leslie, have you ever had a problem in space, that could have turned out in disaster?
Well, that is an easy question for me to answer considering that I have not been in space. So, I have never experienced any problems. But, there does exist the possiblity of space causing a problem for the astronauts in space, so that is why redundancy of every shuttle system is built into the Space Shuttle.

[ Frank/KSCWeatherOffice - 146 - 10:56:31 ]
RE: [KenSchrock/MSFC] The X stands for eXperimental and they are always the first of a type of vehicle that started with a theory that needs investigating. You could call the Wright Brothers airplane an X vehicle because they used it to test theories and further the knowledge base of the design of aerospace vehicles. The first numbered X vehicle was the X-1 which Chuck Yeager flew to supersonic (greater than Mach 1) speeds. I'm currently associated with X-33, -34, -37 and 40A X vehicles. All of these are reusable launch vehicle demonstrators. X-31 and X-36 were out at Dryden when I was there, but I didn't work with them much. They were more focused on aircraft maneuvarability investigations.
Brian - The weather team here at Kennedy also works on the X-planes. We help them develop their own weather rules and determine what weather instruments and support they will need to operate their vehicles safely.

[ AndyPetro/JSC - 147 - 10:56:59 ]
RE: [KayleeandAmie] Did any of you know the astronauts that died when the space shuttle exploded on the way down GRADE 7 STUDENTS
I worked in crew training at the time of the Challenger accident and knew all of the crew members to some degree. I had worked closely with Judy Resnick on her earlier flight. It was a great loss.

[ Leslie_Ringo - 148 - 10:57:53 ]
RE: [JosueNashuaNH] What type of material do you make the shuttle windows from?
I know the windows are made of a special glass. They have 3 separate windows layers that an astronaut looks through. They each have a special function such as maintaining the interior cabin pressure to filtering out bad ultraviolet lights.

[ AndyPetro/JSC - 149 - 10:58:16 ]
RE: [jennifer] could there be another satalight to mars
We will continue sending spacecraft to Mars every two years when the planets line up right. We may skip the next time since they want to fix any problems that could lead to a failure like the one we just had.

[ Leslie_Ringo - 150 - 10:58:37 ]
RE: [KayleeSchafers] Leslie, If you were offered 1 millian dollars, would you change your job? Grade 7 student
In a heart beat yes. Wouldn't you change your job if you were offered a million dollars?

[ AndyPetro/JSC - 151 - 10:59:21 ]
RE: [GailandLindsay] Dear Mr. Petro does glass break in space from the pressure?
It won't break if it is the right kind of glass and it is thick enough. Most spacecraft have windows. The Space Shuttle windows have three panes - just in case.

[ Frank/KSCWeatherOffice - 152 - 10:59:24 ]
RE: [Kelly] Frank Merceret, What is the most dangerous weather conditions to land in? What is the most dangerous to take off in? What makes these weather conditions so dangerous? 8th grade
Kely - The most dangerous condition to land in would be a thunderstorm. That's why our rules won't allow a landing if there are thunderstorms anywhere within 20 miles of the landing site. Thunderstorms have high, gusty winds which could blow a Shuttle off of the runway, turbulence which could make it difficult to control, and lightning which could knock out the electrical systems and computers which control the Shuttle.

[ AndyPetro/JSC - 153 - 11:00:42 ]
RE: [GailandLindsay] Dear Mr. Petro when you get to Earth are you dizzy from being in 0 gravity?
When astronauts come back to Earth they do take some time to adjust to gravity again. It makes them feel tired but they are usually back to normal in a few days.

[ AndyPetro/JSC - 154 - 11:01:26 ]
RE: [KayleeSchafers] If there was a medical crysis in space what would you do?
The Shuttle can come back to Earth pretty quickly if there is a problem.

[ Leslie_Ringo - 155 - 11:02:03 ]
RE: [Shellye] Do you you have to have a PhD to be an astronaut?
You do not have to have a PhD to be astronaut, but it does help. If you want to be a commander or a pilot for a shuttle mission, you do need to have military test pilot background with several thousand hours of high performance jet aircraft time. To be a mission specialist, those are the positions that typically require the PhD skill levels.

[ Leslie_Ringo - 163 - 11:04:33 ]
RE: [Kate] What are the different locations for landing?
There are several locations for landing. The two main sights are either Kennedy Space Center (Flordia) or Edwards Air Force Base (California). For emergency landing sites, there are locations around the world available for the shuttle to land at. The are sites called "TAL" for trans-atlantic landing sites, and also sites called "ECAL" for east-coast landing sites located within the US or Canada.

[ Frank/KSCWeatherOffice - 164 - 11:05:10 ]
RE: [Brittanyterra] Leslie does your job get you really tired?
It certainly can at times. I support not only Shuttle launches but also launches from Cape Canaveral of Titan, Atlas and Delta rockets. These all can occur any time of day - or night - or on weekends. On some occasions I have stayed up all night for an early morning launch which was scrubbed at 4 AM, and had do do it all over again the next day. But it is worth it to be part of such an exciting and valuable program.

[ AndyPetro/JSC - 165 - 11:05:45 ]
RE: [Kelly] Andy Petro, What project that you have worked on has been your favorite? Why was it your favorite? What was your favorite spacecraft that you designed? 8th grade
My favorite project is the one I work on now - the plasma rocket because it is a really advanced technology but we get to actually build things in the laboratory right now. And I am learning new things every day. My favorite spacecraft design was a reusable capsule for people - but like many new designs, it may never be built - but I still like it.

[ KenSchrock/MSFC - 166 - 11:05:56 ]
RE: [Randy] mr. Schrock how are the maps from the telescope
Randy, it looks like your question was cut off. I'll try and guess where you were going with your question. The Shuttle Radar Topography Mission had a radar transmitter and receiver. One was on the end of a 190 foot boom that was the largest space structure ever deployed. By keeping VERY precise track of where the shuttle was, a map could be built up point by point. It used the time it took for a radar signal to go out from the transmitter, reflect off the earth, and then get back to the receiver. Taking the speed of light, divided by half of that total time (up and back is twice the distance) could be used to figure the distance. Coordinating all of those points from where the shuttle was, and where its radar was pointing is how they will build up a new, global elevation map of the world. I'm sure it will take several months for computers to go through all the algebra and geometry to do this. Are you noticing the recurring theme that you need lots of math, physics and computer programming classes to do NASA engineering work? We want all of you to study hard and come work side by side with us in the future. :-)

[ Leslie_Ringo - 167 - 11:06:39 ]
RE: [Tory] How many shuttles are there?
Shuttles: Enterprise (never flown in space), Columbia, Discovery, Atlantis and Endevour.

[ Frank/KSCWeatherOffice - 168 - 11:07:01 ]
RE: [Gailandlindsay] Have sattelites ran into shuttles before?
No. The Department of Defense tracks all of the satellites and most of the debris in space. They calculate any possible collisions and warn the Shuttle so it can maneuver to avoid any threat.

[ AndyPetro/JSC - 173 - 11:07:13 ]
RE: [Gailandlindsay] Have sattelites ran into shuttles before?
The Shuttle has never run into a satellite. They keep track of these things and maneuver the Shuttle to avoid a collision if they have to. The Shuttle has been hit by timy particles in orbit but there was no serious damage.

[ Leslie_Ringo - 174 - 11:08:12 ]
RE: [Brittanyterra] Leslie does your job get you really tired?
No, I never get tired of my job. I am alway working on a new project every 3-6 months, so you do not get bored of working on one project year after year. Having a change every now and then is a good thing. It constantly keeps you on your toes and you are always learning new things.

[ Leslie_Ringo - 175 - 11:09:59 ]
RE: [marilyn] When the shuttle is on the launch pad are they still talking to Houston?
When the shuttle is on the launch pad, Houston does have the ability to talk with the shuttle, but it is Kennedy Space Center that is in control of all shuttle operations until the shuttle is launched.

[ AndyPetro/JSC - 176 - 11:10:04 ]
RE: [Randy] will NASA ever use solar power for space shuttles
Probably not, but there was an idea to fold out a solar panel from the Shuttle so that it would have extra power during a very long mission. There are no plans to do that now but it is still a good idea. The Russian Soyuz spacecraft uses solar panels and the Mir and International Space Station also use solar power.

[ Frank/KSCWeatherOffice - 181 - 11:12:28 ]
RE: [soehlms] Frank: Exactly what kind of pressure do you and your team feel as the launch approaches, the weather is marginal, and you have to decide whether to stop the countdown? Are things very intense, or is there all kinds of strategies to use to keep calm?
The Shuttle weather team (Air Force and National Weather Service)is under a great deal of pressure if the weather is marginal. If the weather is really great or really terrible, things are easy. It's in the middle that things get tough. The Air Force at the Cape and the Spaceflight Meteorology Group at Houston both have teams of people, not just a single forecaster, working the details of the weather and of the launch and landing weather rules. They also have support contractors helping keep the instruments and data processors working. They are in constant contact with the mission management team throughout the countdown via a communications net and also by phone. The closer the call, the higher the tension. The rule is that we must be "CLEARLY CONVINCED" that it is SAFE to fly -- or we don't fly!

[ AndyPetro/JSC - 182 - 11:12:31 ]
RE: [Tory] What is the average payload that is received per shuttle mission?
The shuttle usually carries payloads that can weigh up to about 50,000 pounds - but often there is more than one payload at a time.

[ Leslie_Ringo - 183 - 11:14:11 ]
RE: [Tory] Do you ever think space travel will be commercialized as a vacation type trip?
That is an interesting question. If you think about it, in the early 1900's, the Wright brothers were flying and today we have commercial airliners. There are several issues to be worked out before space travel available for the general public. I don't see it happening anytime soon, but I would not say that it would "never" happen.

[ Frank/KSCWeatherOffice - 184 - 11:14:12 ]
RE: [Emily] Is there any condition in the weather that you can not have the shuttle lift off? If so, what are they?
Emily - We can't launch in rain, high winds, very cold temperatures, or when there is any threat of lightning. The actual rules are complicated and fill up a small booklet!

[ AndyPetro/JSC - 185 - 11:14:33 ]
RE: [GailandLindsay] Dear mr. Petro can you bring things back to keep in your home from space?
I am not an astronaut but I have received things like flags that have been flown in space as gifts. Astronauts do keep some of the things that they carry into space but they are not allowed to make money by selling these things.

[ KenSchrock/MSFC - 186 - 11:15:40 ]
RE: [Gailandlindsay] Have sattelites ran into shuttles before?
Two spacecraft running in to each other would be disastrous. Two cars bumping in to each other in a parking lot a 10 miles per hour can cause a lot of damage from the energy absorbed by the vehicle. If you have something in orbit at 18,000 miles per hour and it meets something coming from the othere way at 18,000 miles per hour, you're are talking about some serious energy to be absorved. The formula for kinetic energy is K=1/2mv^2 algebraically or one half multiplied times the mass times the velocity times the velocity. Okay, now that I've scared you talking about the energy, let me tell you that there are many people whose entire job is to track what's in space. They see where it is and describe its orbit. They also track how big it is. Then they publish the information for anyone that needs it. The internet is great for this kind of distribution. You can get a great tool for free that does orbital mechanics and they have special programs just for school. Go to www.stk.com and click around for educators. They will send anyone the program, and their web site is updated three times per week with what's going on in orbit.

[ Leslie_Ringo - 187 - 11:16:05 ]
RE: [GailandLindsay] Dear mr. Petro can you bring things back to keep in your home from space?
I don't think astronauts can "find" something and bring back home to keep as a momento in their home. What astronauts can do is take a personal item of theirs (small) into space, and bring that back home. Then they can say it flew in space.

[ AndyPetro/JSC - 193 - 11:16:28 ]
RE: [KayleeandAmie] How much money does it usually cost to send people to space?
A space shuttle flight with seven people costs a few hundred million dollars. Launching three people in a Russian Soyuz vehicle costs a lot less but still about 50 million dollars. We hope that eventually these flights will get a lot less expensive.

[ Frank/KSCWeatherOffice - 194 - 11:16:37 ]
RE: [MrsLatinaNashuaNH] Does the Shuttle send back any information about the Earth's weather for scientists to study?
Shuttle experiments over the last 20 years have brought back a wealth of weather information. One of the new fields of weather study which got its start based on Shuttle observations is the study of lightning-related discharges propagating UPWARD from the tops of thunderstorms. THese "blue jets" and "red sprites" were essentially unknown until observations from space captured them on film and video. Now scientists on the ground are also studying them.

[ AndyPetro/JSC - 195 - 11:17:57 ]
RE: [angus] What's next after the space shuttle? Is there any cool new space travel ships in devolpment?
There is a "next-generation" shuttle on the drawing board but I expect the most exciting new vehicles will be private vetures.

[ AndyPetro/JSC - 196 - 11:19:10 ]
RE: [Tory] Andy, is their the possibility of humans leaving our solar system in Shuttles?
Not in the space shuttle. It is meant just for getting of the Earth and few hundred miles up. We will need a different kind of space ship to travel to the outer solar system and beyond. (That is what I'm working on.)

[ Leslie_Ringo - 197 - 11:19:12 ]
RE: [Tory] How high tech are the computers aboard a shuttle? WHat year are most of them?
The technology of the space shuttle in general is a replication of 1970's technology. Remember, that was when the shuttles were built (1973-1979). There have been some upgrades, but the Space Shuttle is a "tried and true" tested machine and engineers are very reluctant to try something experimental on the shuttle. The number one goal is to keep the shuttle a safe vehicle.

[ AndyPetro/JSC - 203 - 11:21:40 ]
RE: [HannahL] What is the highest speed your rockets reach?
Most rockets going into Earth orbit end up at 18,000 miles per hour. If they leave orbit they are going about 25,000 miles per hour. Some spacecraft that have used the gravity of Jupiter to speed up have gotten above 100,000 miles per hour.

[ Leslie_Ringo - 204 - 11:22:53 ]
RE: [Tory] What is the most amount of people that can be comfortably fit into a shuttle?
7 is the current limit that can be launched into space. If there should be an emergency rescue mission to a space station, the shuttle could bring a total of 8 people back. In addition to the shuttle being a rescue vehicle, there will be crew return vehicles on the space station to serve as emergency return vehicles.

[ KenSchrock/MSFC - 205 - 11:22:54 ]
RE: [angus] What's next after the space shuttle? Is there any cool new space travel ships in devolpment?
Angus, There are definitely cool space ships in works for the next generation launch vehicles. NASA Marshall's charter includes designing future launch vehicles. Start at www.msfc.nasa.gov and you'll find links to the advanced space transportation program. Some of the things I'm working on now is research that will go in to the vehicles we'll be building fifty years from now. I'll probably retire in about thirty years so we need more people to become engineers and help us build those vehicles. Will you be one of them?

[ AndyPetro/JSC - 206 - 11:24:11 ]
RE: [Reid] Dear Andrew Petro, What are some of the projects you have been involved in?
I have worked on crew training for the Space Shuttle, worked on designs for new launch vehicles and spacecraft, ships for going to the Moon and Mars, and bases for the Moon. I have also worked with the Russians on using their spacecraft as part of the new space station. Now I work on the plasma rocket for interplanetary flight.

[ Leslie_Ringo - 207 - 11:24:12 ]
RE: [KayleeandAmie] Can you keep pets in space?
I don't know if you would call them "pets", but the Space Shuttle has had several experimental missions where they have flown up either bugs or animals. I know on mission STS-90, they took up baby rats.

[ AndyPetro/JSC - 208 - 11:25:16 ]
RE: [Randy] when will the international space station go up.
The first two parts are already up there! They will be sending up more parts this year and then a crew will begin living and working there. The assembly will continue for several years.

[ Leslie_Ringo - 209 - 11:25:26 ]
RE: [Randy] when will the international space station go up.
The Space Station is actually already orbiting around Earth. The next couple of years we will be adding on crew modules and other pieces to make the Space Station a more functional living environment.

[ Leslie_Ringo - 215 - 11:27:52 ]
RE: [marilyn] In your simulator can you simulate the atmospheres from other planets. In other words, could you 'fly' a Joint Strike Fighter on Mars?
Actually, we can simulate anything that we have a "math model" for. So, we could easily model the atmosphere and fly the Joint Strike Figher on Mars, but that would not provide much research information to the folks designing the JSF.

[ AndyPetro/JSC - 216 - 11:28:03 ]
RE: [Ashley] What year would you estimate that we could actually have people living in space?
People have lived on the Mir space station continuously since 1986 until recently. By the end of this year there should be be people living on the new space station - then there may never be another time when people aren't living in space.

[ KenSchrock/MSFC - 217 - 11:28:06 ]
RE: [Laura] What happens if the machinery to keep track of the shuttle fails?
As I mentioned in a previous answer, good engineering design builds in redudancy so the shuttle isn't stranded. Part of our work is to do fault analysis, which is where the people that work most with a system use their skill to determine what parts could fail, and what to do if they did. You don't just assume that there won't be any problems and that you are done designing a system. Part of your job responsibility is to track what could go wrong and report ways that it could be fixed.

[ AndyPetro/JSC - 222 - 11:29:42 ]
RE: [Calvin] Can you bring CDs or videogames into space with you?
Sure. They use videotapes and laptop computers so CD's and games should be no problem.

[ Leslie_Ringo - 223 - 11:29:52 ]
RE: [Tory] Leslie, I have heard in cartoons and movies where people make civilizations in outer space, do you ever see this a reality?
As for having civilations in outer space, it think it is more of a matter of when as opposed to if it will happen. If their is the drive to make this a reality, I don't doubt it would happen.

[ AndyPetro/JSC - 224 - 11:31:07 ]
RE: [Tory] Mr.Petro, I am under the impression you only have been in simulators, do you intend to ever go into space and why?
I am an engineer who works on the design of spacecraft and rockets. I am not an astronaut. I would like to travel in space someday but that is not my job right now.

[ Leslie_Ringo - 225 - 11:31:30 ]
RE: [Ellen8] Why was Alan Shephard not considered to be in actual orbit? Had he not passed into the blackness of space?
On Alan Shephard's first manned flight into space, he probably did reach the "blackness of space" but did not do a complete orbit around the earth before returning.

[ Leslie_Ringo - 226 - 11:32:40 ]
RE: [Brittny] Do any of you have strong role models?
My strongest role models would be my parents. They pushed me and as a result, I am where I am today.

[ AndyPetro/JSC - 227 - 11:33:12 ]
RE: [Ellen8] Why was Alan Shephard not considered to be in actual orbit? Had he not passed into the blackness of space?
Going into orbit means coasting in a complete circle around the Earth. Alan Sheppard's first flight was just a lob up very high and back down a few hundred miles away. he was in space but not in orbit. Alan Sheppard later made a flight to the Moon.

[ Leslie_Ringo - 234 - 11:33:30 ]
RE: [KayleeandAmie] Do you know Julie Payette?
I do not know Julie Payette.

[ Leslie_Ringo - 235 - 11:33:50 ]
RE: [Randy] Where do the boosters land?
They land in the Atlantic Ocean.

[ AndyPetro/JSC - 236 - 11:34:34 ]
RE: [Kate] How much does it cost to do an experiment, like sending a crew to the Hubble Space Telescope?
About 500 million dollars.

[ KenSchrock/MSFC - 237 - 11:35:15 ]
RE: [Ellen8] Why was Alan Shephard not considered to be in actual orbit? Had he not passed into the blackness of space?
Alan Shephard and Gus Grissom were on sub-orbital trajectories. This means they did not have enough speed to maintain orbit and earth's gravity pulled them back in. They did earn their astronaut wings because of the altitude that they did make. Also many of the X-15 pilots earned astronaut wings because of their altitude. I've talked to SR-71 blackbird pilots that said at "just" around 80,000 feet the sky has turned black rather than blue so there would still be the feeling of being in space.

[ Leslie_Ringo - 238 - 11:35:44 ]
RE: [marilyn] After the training how do you know that an astronaut is REALLY ready to fly?
The astronauts spend years of training with several trainers. It is this group of trainers and the astronaut's supervisors who make the call if the astronauts are "REALLY" ready for a mission.

[ Ashley - 240 - 11:36:12 ]
What do you like to do in your spare time? Is there a recreation center?

[ Alex - 241 - 11:36:12 ]
Does the weather affect the space ship in space?

[ AndyPetro/JSC - 243 - 11:36:16 ]
RE: [satoshi] I was wondering what material the shuttle is made of.
It is mostly made of aluminum but the outside is is covered with tiles made of silica (kind of like glass) on the bottom and insulating blankets on top.

[ Leslie_Ringo - 244 - 11:37:45 ]
RE: [satoshi] I was wondering what material the shuttle is made of.
The shuttle is made of almost every type of material available. From titanium, to aluminum, to ceramic tiles, to rubber heat sinks, to insulating blankets, etc. This list is too long.

[ David - 245 - 11:39:16 ]
Has there ever been a problem guiding a shuttle back home?

[ Ben - 246 - 11:39:16 ]
How do you bathe in space? 8th grade

[ Leslie_Ringo - 250 - 11:39:17 ]
RE: [Tory] I really wonder, about how many square feet of living space is on a shuttle?
I don't know the exact number, but it is a very very small area for 7 people. In the upper deck, it is very hard to stand tall. You'll bumb your head first.

[ AndyPetro/JSC - 251 - 11:39:26 ]
RE: [Tory] I really wonder, about how many square feet of living space is on a shuttle?
The Shuttle has about 70 cubic meters of volume for the people. You will have to calculate what that is in cubic feet.

[ Leslie_Ringo - 252 - 11:40:19 ]
Thanks for all the interesting question. I had fun talking with everyone. I need to get back to work so have fun talking with the other experts. :)

[ AndyPetro/JSC - 253 - 11:40:47 ]
RE: [GailandLindsay] Andrew petro have you been in the space program most of your life?
I have been since I graduated from college - and I was interested in it for as long as I can remember.

[ Oran/NASAChatHost - 254 - 11:41:54 ]
RE: [Leslie_Ringo] Thanks for all the interesting question. I had fun talking with everyone. I need to get back to work so have fun talking with the other experts. :)
Leslie, we thank you so much for participating in today's panel discussion. We look forward to chatting with you again on Tuesday, March 21. Have a great day!

[ AndyPetro/JSC - 255 - 11:42:14 ]
RE: [Tory] What would be the best part of day to spend in space?
A lot of astronauts say that the sunsets are the most impressive thing to see - and that happens every 90 minutes.

[ KenSchrock/MSFC - 256 - 11:42:57 ]
RE: [Amy8] Dear Ken Schrock, Does the Global Positioning System have any part in the new Space Station?
The space station does use a special GPS receiver that can determine its attitude, or orientation. The attitude information is fed back in to the Guidance Navigation and Control computers to help position the stations where the experiments need it to be. There are people at NASA Johnson and I believe Goddard that work on station GPS attitude and positioning. I haven't done any work yet with an attitude determination receiver yet, but I've a got a unit that I plan to do some experiments with soon.

[ AndyPetro/JSC - 257 - 11:44:12 ]
RE: [KayleeandAmie] If I started Space Training now how old will I be when I could go on a mission. We are 13 now.
I think that you will need to finish college and then get some other experience. Most people are in their thirties when they get selected as astronauts. Maybe in the future more people will get to go and they will be younger.

[ AndyPetro/JSC - 264 - 11:45:38 ]
This has been a great session but I think I better get back to work. Thanks for the great questions.

[ Oran/NASAChatHost - 265 - 11:46:56 ]
RE: [AndyPetro/JSC] This has been a great session but I think I better get back to work. Thanks for the great questions.
Andy, our thanks to you for joining us for today's panel discussion. We look forward to chatting with you as a featured NASA expert in the future. Have a good day!

[ KenSchrock/MSFC - 267 - 11:49:08 ]
RE: [GailandLindsayandDanandPaul] Dear mr. PetroWhat causes the double sonic boom on reentering?
Sorry if I'm doubly answering this question, but the double boom comes first from the compression wave in front of the vehicle and the second way from the expansion wave behind the vehicle. When I lived on the California coast, I could hear the double booms when the shuttle was landing at Edwards.

[ KenSchrock/MSFC - 268 - 11:53:12 ]
RE: [Kate] Mr. Schrock, who is your astronaut hero?
One of them would be Neal Armstrong because he was an engineer, flew the X-15, and, well you know the other thing. Another would be Mission Specialist Steve Hawley because he's from Kansas and he personally gave me some encouragement after speaking and the Kansas Cosmosphere and Space Center.

[ KenSchrock/MSFC - 269 - 11:58:16 ]
RE: [marilyn] When I was a kid I heard Scott Crossfield asked the question, "What would happen if the protective cover for its landing skid didn't deploy." He wryly answered, "I guess we' have the most expensive plow in the world."
I'm not sure I understand the question, but Scott Crossfield flew lots of X-vehicles. If he couldn't get lined up for the runway and slowed down, he would have come in very fast with lots of energy and a high sink rate. In other words it dug a deep hole where it impacted and would still have some forward energy. He was making a joke about crashing and diggin a long, straight trough.

[ Oran/NASAChatHost - 270 - 11:58:19 ]
This concludes today's NASA Quest Space Team Online/Classroom Connect panel discussion. We would like to thank all our chatters for their great questions. We also extend our very special thanks to our featured panelists for sharing their career expertise and thoughtful responses to our questions. THANK YOU, NASA Experts!

[ soehlms - 271 - 11:58:35 ]
Thanks so much to all of you for this chat!!!! From, Soehl Middle School, Linden, NJ

[ KenSchrock/MSFC - 272 - 12:03:34 ]
RE: [Alex] Does the weather affect the space ship in space?
When you say weather, I assume you mean things like wind and thunderstorms. Our atmosphere protects us from many things outside of the earth. It only goes up so high however. I think thunderstorms only go up to maybe 70,000 feet high, 10-15 miles (I'm doing this in my head) while shuttle and station are up around 200 miles. There is a space atmosphere or environment. There is solar wind coming from the sun, and cosmic radiation from deep space. Solar cycles can heat up and expand the atmosphere. Low Earth Orbit spacecraft do have to consider the expanded atmosphere in long term station keeping. It was because of solar cycles and the expanded atmosphere's drag that brought down skylab.

[ Brian - 273 - 12:03:39 ]
If you want to talk about the chats and what you learned, go to the Classroom Today Message Board at: http://classroomtoday.com/messageboard